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RT Classic reg piston and Reg seat questions

I have a couple regulator questions:

1) While taking apart my RT i was unable to remove the regulator piston assembly without unscrewing the tiny allen set screw on the outside of the regulator housing. I thought this set screw was only to lock the valve into the Z - slot, does it do anything else? should it be so tight that it touches the regulator piston?

2) In the video that came with the gun, the regulator seat appears to set down into a recessed area tight enough to stay on the regulator body. Mine does not do that, it will fall right out. The other side, the o-ring side, does fit tightly around the regulator valve pin, though. Is anything wrong with mine, or just a slightly different model?

Apparently, the zlock pin has been changed to a set screw. If someone drilled it out too far and had to put a screw in there it would be possible to hit the reg piston if screwed in to far. Install the regulator valve pin all the way in. If it sticks out too far the reg seat oring will not seat in the groove. If you can get it down in there and it is loose then change the oring.

Apparently, the zlock pin has been changed to a set screw. If someone drilled it out too far and had to put a screw in there it would be possible to hit the reg piston if screwed in to far.

If that's a #6 setscrew, you might be able to put a 1/8" diameter roll pin back in there. Either way, you should check the fit so that it fits in the rail without touching the reg piston (grind it or file it), then install it with some red loctite. It shouldn't be a problem after that. The vibration from shooting will make a loose pin or screw move one way or the other.

Apparently, the zlock pin has been changed to a set screw. If someone drilled it out too far and had to put a screw in there it would be possible to hit the reg piston if screwed in to far. Install the regulator valve pin all the way in. If it sticks out too far the reg seat oring will not seat in the groove. If you can get it down in there and it is loose then change the oring.

So the set screw is not factory? Even on the early models? I'm pretty sure this hasn't been changed, I've owned the gun for over 10 years. Basically though, it is not there to hold the reg piston in place, correct? As in it should not be that tight?

The valve pin sits fine, and the o-ring side of the regulator seat sits fine. It is the other side of the regulator seat that just sits flush with the regulator housing, the black part. It does not sit in a groove at all, really there is no groove there.

If that's a #6 setscrew, you might be able to put a 1/8" diameter roll pin back in there. Either way, you should check the fit so that it fits in the rail without touching the reg piston (grind it or file it), then install it with some red loctite. It shouldn't be a problem after that. The vibration from shooting will make a loose pin or screw move one way or the other.

Thanks for the reply. Is there any problem leaving it as a set screw? Once I backed it off a little the reg piston fell right out. There should be no leak potential there, right?

Does the reg piston still have an o-ring on it? Usually you have coax them out a little bit.

You might want to post a pic of the reg seat you are describing.

Yes, the piston has an o-ring. I used the allen wrench to push it out. It would not budge initially, so I got the idea to loosen the set screw, which worked. When re-assembling, I wasn't sure if I needed to tighten that set screw back down.

The pic in the op is of the o-ring side of the reg seat, and the black housing that it sits on. The video, and others on here, have mentioned that the reg seat should sit down in a recessed area in the housing. Mine has no area like that, the reg valve pin holds the seat in place. Here is another pic of the seat.

Yes, the piston has an o-ring. I used the allen wrench to push it out. It would not budge initially, so I got the idea to loosen the set screw, which worked. When re-assembling, I wasn't sure if I needed to tighten that set screw back down.

The pic in the op is of the o-ring side of the reg seat, and the black housing that it sits on. The video, and others on here, have mentioned that the reg seat should sit down in a recessed area in the housing. Mine has no area like that, the reg valve pin holds the seat in place. Here is another pic of the seat.

Thanks for the help, sorry for the poor descriptions!

You definitely need to loctite that set screw. It would chew on the piston if it turned in.

It's hard to tell from that angle. Look at this animation. The groove is open, but the o-ring sits in there.

Yes. But the reg seat oring is the larger one that goes below that reg seat holder. It gets installed in the valve before you drop the holder on. The little oring also gets installed in the other half of the valve before screwing the valve halves together.

Sorry again for the poor descriptions. Below is a link to the video I have been using to help me. Beginning at 8:20, you can see how the reg seat holder sits on the black part. Mine won't, nothing there to hold it. No recessed area.

Sorry again for the poor descriptions. Below is a link to the video I have been using to help me. Beginning at 8:20, you can see how the reg seat holder sits on the black part. Mine won't, nothing there to hold it. No recessed area.

DAMN thats a old Valve dood!!! your not giving poor descriptions...its a different valve...the reg seat holder in the video is just located on tha regulator half, but you have the correct name tho! wats the valve number on that grey haired valve

on current valves the reg seat holder is located on the valve half...thats probably where there was some confusion about the reg seat holder?

DAMN thats a old Valve dood!!! your not giving poor descriptions...its a different valve...the reg seat holder in the video is just located on tha regulator half, but you have the correct name tho! wats the valve number on that grey haired valve

on current valves the reg seat holder is located on the valve half...thats probably where there was some confusion about the reg seat holder?

any updates?

The number on the valve is RTO4507. Thanks for the explanation, I was hoping nothing was wrong! No real updates, gassed it back up on Friday and she still leaks, I have another thread going on trying to solve that issue... The poor gun has been barely used...I bought it, played for 2 months, then went to college and lost it in the move, 12 yrs ago. Just found it this winter. It worked great before I lost it, but now I am dealing with all sorts of problems. I am figuring them out bit by bit though.

Where are the leaks? Down the barrel? Out the back? Around the valve halves... this is the same rt with the on off problem in the other thread right?

When I first gassed mine up (sat for 8 years) it leaked from every place it could. I bought a parts kit for $16 and replaced every oring no matter if it looked good or not. Still have enough for another rebuild from the kit.

It sounds like your on the right path, id just go through each section of the valve at a time. Clean/ new orings in the power tube, then clean/ new orings in the on off etc... use lots of oil and then shoot it about 30 times with the barrel off and all the excess will get shot out keep us posted.

I know how the frustration goes. After not fiddling with my mag for almost a decade I tore it down and rebuilt it, put the on off pin in backwards, it would charge air till it leaked out the back and then when I pulled the trigger it sounded like the velocity was about 500fps, lol. You'll get it

Where are the leaks? Down the barrel? Out the back? Around the valve halves... this is the same rt with the on off problem in the other thread right?

When I first gassed mine up (sat for 8 years) it leaked from every place it could. I bought a parts kit for $16 and replaced every oring no matter if it looked good or not. Still have enough for another rebuild from the kit.

It sounds like your on the right path, id just go through each section of the valve at a time. Clean/ new orings in the power tube, then clean/ new orings in the on off etc... use lots of oil and then shoot it about 30 times with the barrel off and all the excess will get shot out keep us posted.

I know how the frustration goes. After not fiddling with my mag for almost a decade I tore it down and rebuilt it, put the on off pin in backwards, it would charge air till it leaked out the back and then when I pulled the trigger it sounded like the velocity was about 500fps, lol. You'll get it

Thanks for the encouragement. It started as a MAJOR, empty-the-tank-in-about-3-seconds leak, but I have most of that fixed. Now it leaks a little until the trigger is pulled, then it stops. That tells me it is an on-off bottom or middle o-ring or the power tube o-ring. Pushing on the bolt from the barrel end didnt change the leak, so I'm thinking on-off. All of the o-rings are brand new, so I just cleaned it out a little better. We'll see. My other threads are about the sear and about the banjo bolt.